Transition metal compound, polymerization catalyst using same and process for producing styrenic polymer using said polymerization catalyst

ABSTRACT

There are disclosed a transition metal compound of the general formula RMX a-1  L b  (R is a π ligand, a fused polycyclic cyclopentadienyl group in which at least one of many-membered rings to which cyclopentadienyl groups are fusedly bonded is a saturated ring, M is a transition metal, X is a σ ligand, L is a Lewis base, a is the valency of M, and b is 0, 1 or 2); a polymerization catalyst for styrene, etc. comprising the above transition metal, preferably further comprising an oxygen atom containing compound ionic compound or organoboron compound and optionally a Lewis base; and a process for producing a polymer of a compound containing an ethylenically unsaturated double bond or an acetylenic polymer, especially a syndiotactic polystyrene by using the above polymerization catalyst. The catalyst is particularly effective for producing highly syndiotactic polystyrene minimized in residual metals amounts at a low cost in enhanced efficiency.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a transition metal compound, apolymerization catalyst using the same and a process for producing astyrenic polymer using said catalyst. More particularly, it pertains toa transition metal compound which is useful as a component of apolymerization catalyst for a compound containing an ethylenicallyunsaturated double bond or acetylene series, especially of apolymerization catalyst for styrene series; a highly activepolymerization catalysts which contains the above-mentioned transitionmetal compound and serves for a compound containing an ethylenicallyunsaturated double bond or acetylene series; and a process forefficiently producing at a low cost, a styrenic polymer which has a highdegree of syndiotactic configuration and is minimized in the amounts ofresidual metals by the use of the aforesaid polymerization catalyst.

2. Description of Related Arts

Olefinic polymers such as polyethylene and polypropylene find theirgreat use as a general-purpose resin in a variety of fields. It is knownthat the aforesaid olefinic polymers are produced in the presence of acatalytic system containing Ziegler-Natta catalyst as a principalcatalytic component. Recently an attempt is made to produce an olefinicpolymer by the use of a polymerization catalyst comprising as acatalytic component, a transition metal compound having a π ligand inwhich said π ligand is bonded to a central metallic element through anarbitrary group.

For example, there are disclosed catalysts for olefins polymerizationcomprising a catalytic component, a transition metal compound having a πligand in which said π ligand is bonded to a central metallic elementthrough an arbitrary group as well as processes for producing olefinicpolymers by the use of the catalysts in European Patent ApplicationLaid-Open Nos. 420436, 418044, 416815, 468651, 495375, 514828 and520732, International Publication No. 00333/1992, etc.

However, sufficiently satisfactory catalytic-activity has not beenobtained from a catalyst among them comprising a transition metalcompound in which the π ligand is a fused polycyclic cyclopentadienylgroup containing an aromatic ring such as indenyl group or fluroenylgroup.

Heretofore, styrenic polymers produced by the radical polymerizationmethod or the like have an atactic configuration in stereostructure andare molded to various shapes by various molding methods such asinjection molding, extrusion molding, blow molding, vacuum molding andcast molding, and they have been widely used as domestic electricalappliances, office machines, household goods, packaging containers,toys, furnitures, synthetic papers, sheets, films and other industrialmaterials.

However, such styrenic polymers having atactic configuration havedisadvantage that it is inferior in heat resistance and chemicalresistance. On the other hand, since the styrene polymers having asyndiotactic configuration have melting points which are different fromthose of the conventional atactic polystyrenes, and are higher thanthose of the isotactic polystyrenes known so far, they are expected tobe used as heat-resistant resins in various fields.

The group to which the present inventors belong has previously foundthat the use of a combined catalyst of an aluminoxane with a transitionmetal compound having an indenyl group as a π ligand can produce astyrenic polymer having a syndiotactic configuration (refer to JapanesePatent Application Laid-Open No. 294705/1989). However, the catalystcomprising the transition metal compound containing, as a π ligand, afused polycyclic cyclopentadienyl group having an aromatic ring such asan indenyl group suffers a disadvantage that the catalyst fails toattain a sufficient catalytic activity.

SUMMARY OF THE INVENTION

Under such circumstances, it is an object of the present invention toprovide a novel transition metal compound which is useful as a componentof a polymerization catalyst for a compound containing an ethylenicallyunsaturated double bond or acetylene series, especially of apolymerization catalyst for styrene series.

It is another object of the present invention to provide a highly activepolymerization catalyst which comprises the above-mentioned transitionmetal compound and serves for a compound containing an ethylenicallyunsaturated double bond or acetylene series.

It is a further object of the present invention to provide a process forefficiently producing at a low cost, a styrenic polymer which has a highdegree of syndiotactic configuration and is minimized in the amounts ofresidual metals by the use of the aforesaid polymerization catalyst.

In order to achieve the above-mentioned objects, intensive research andinvestigation were continued by the present inventors. As a result, ithas been found that a transition metal compound of a specificconstitution having, as a π ligand, a fused polycyclic cyclopentadienylgroup in which at least one of many-membered rings to whichcyclopentadienyl groups are fusedly bonded is a saturated ring is usefulas a component of a polymerization catalyst for a compound containing anethylenically unsaturated double bond or acetylene series; that apolymerization catalyst which comprises in combination, theabove-mentioned transition metal, at least one from an oxygen atomcontaining compound, a specified ionic compound and an organoboroncompound and optionally a Lewis acid possesses a high activity andthereby can efficiently polymerize a compound containing anethylenically unsaturated double bond or acetylene series; and inparticular that a styrenic polymer which has a high degree ofsyndiotactic configuration and is minimized in the amounts of residualmetals is efficiently obtained at a low cost by polymerizing a styrenicpolymer using the aforesaid polymerization catalyst. The presentinvention has been accomplished on the basis of the aforestated findingand information.

Specifically, the present invention provides a transition metal compoundwhich is characteristically represented by the general formula (I)

    RMX.sub.a-1 L.sub.b                                        (I)

wherein R is, as a π ligand, a fused polycyclic cyclopentadienyl groupwherein at least one of many-membered rings to which cyclopentadienylgroups are fusedly bonded is a saturated ring, M is a transition metal,X is a σ ligand, a plurality of X may be the same or different andbonded to each other through an arbitrary group, L is a Lewis base, a isthe valency of M, b is 0, 1 or 2 and when L is plural, each L may be thesame or different; a polymerization catalyst for a compound containingan ethylenically unsaturated double bond or acetylene series whichcatalyst comprises the above-mentioned transition metal compound; and aparticularly preferable polymerization catalyst for a compoundcontaining an ethylenically unsaturated double bond or acetylene serieswhich catalyst comprises in combination the above-mentioned (A)transition metal compound; (B) at least one member selected from thegroup consisting of an (1) oxygen atom containing compound, an (2) ioniccompound comprising a noncoordinate anion and a cation and an (3)organoboron compound; and optionally a (C) Lewis acid.

Furthermore, the present invention provides a process for producing astyrenic polymer which comprises polymerizing a styrenic monomer or astyrenic monomer along with an other polymerizable unsaturated compoundin the presence of any of the aforesaid polymerization catalyst andmoreover, a process for producing a polymer of a compound containing anethylenically unsaturated double bond or an acetylenic polymer by usingthe aforesaid polymerization catalyst.

DESCRIPTION OF PREFERRED EMBODIMENTS

The transition metal compound according to the present invention has theconstitution represented by the general formula (I)

    RMX.sub.a-1 L.sub.b                                        (I)

wherein R is, as a π ligand, a fused polycyclic cyclopentadienyl groupin which at least one of many-membered rings to which cyclopentadienylgroups are fusedly bonded is a saturated ring. The above-mentioned fusedpolycyclic cyclopentadienyl group is exemplified by that selected fromthose represented by any one of the general formulae (II) to (IV)##STR1## wherein R¹, R² and R³ are each a hydrogen atom, a halogen atom,an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an aromatichydrocarbon group having 6 to 20 carbon atoms, an alkoxyl group having 1to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, athioalkoxyl group having 1 to 20 carbon atoms, a thioaryloxyl grouphaving 6 to 20 carbon atoms, an amino group, an amide group, a carboxylgroup or an alkylsilyl group and may be the same as or different fromeach other; and c, d, e and f are each an integer of 1 or greater. Ofthese, 4,5,6,7-tetrahydroindenyl group is preferable from the viewpointof catalytic activity and the ease of its synthesis.

Specific examples of R include 4,5,6,7-tetrahydroindenyl group;1-methyl-4,5,6,7-tetrahydroindenyl group;2-methyl-4,5,6,7-tetrahydroindenyl group;1,2-dimethyl-4,5,6,7-tetrahydroindenyl group;1,3-dimethyl-4,5,6,7-tetrahydroindenyl group;1,2,3-trimethyl-4,5,6,7-tetrahydroindenyl group;1,2,3,4,5,6,7-heptamethyl-4,5,6,7-tetrahydroindenyl group;1,2,4,5,6,7-hexamethyl-4,5,6,7-tetrahydroindenyl group;1,3,4,5,6,7-hexamethyl-4,5,6,7-tetrahydroindenyl group;octahydrofluorenyl group; 1,2,3,4-tetrahydrofluorenyl group;9-methyl-1,2,3,4-tetrahydrofluorenyl group; and9-methyl-octahydrofluorenyl group.

M is a transition metal and exemplified by titanium, zirconium, hafnium,lanthanoids, niobium and tantalum. Of these titanium is preferable fromthe viewpoint of catalytic activity, X is a σ ligand and is exemplifiedby a hydrogen atom, a halogen atom, an aliphatic hydrocarbon grouphaving 1 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, anaryloxyl group having 6 to 20 carbon atoms, a thioalkoxy group having 1to 20 carbon atoms, a thioaryloxyl group having 6 to 20 carbon atoms, anamino group, an amide group, a carboxyl group or an alkylsilyl group,and a plurality if X may be the same or different and bonded to eachother through an arbitrary group. Further, X is specifically exemplifiedby hydrogen atom, chlorine atom, bromine atom, iodine atom, methylgroup, benzyl group, phenyl group, trimethylsilylmethyl group, methoxygroup, ethoxy group, phenoxy group, thiomethoxy group, thiophenoxygroup, dimethylamino group and diisopropylamino group. L is a Lewisbase, a is the valency of M and b is 0, 1 or 2.

As the transition metal compound represented by the general formula (I),there can preferably be employed a compound comprising R and X eacharbitrarily selected from the above-exemplified groups.

The transition metal compound represented by the general formula (I) isspecifically exemplified by but not limited to4,5,6,7-tetrahydroindenyltitanium trichloride;4,5,6,7-tetrahydroindenyltrimethyltitanium;4,5,6,7-tetrahydroindenyltribenzyltitanium;4,5,6,7-tetrahydroindenyltitanium trimethoxide;1-methyl-4,5,6,7-tetrahydroindenyltitanium trichloride; 1-methyl-4,5,6,7-tetrahydroindenyltrimethyltitanium;1-methyl-4,5,6,7-tetrahydroindenyltribenzyltitanium;1-methyl-4,5,6,7-tetrahydroindenyltitanium trimethoxide;2-methyl-4,5,6,7-tetrahydroindenyltitanium trichloride;2-methyl-4,5,6,7-tetrahydroindenyltrimethyltitanium;2-methyl-4,5,6,7-tetrahydroindenyltribenzyltitanium;2-methyl-4,5,6,7-tetrahydroindenyltitanium trimethoxide;1,2-dimethyl-4,5,6,7-tetrahydroindenyltitanium trichloride;1,2-dimethyl-4,5,6,7-tetrahydroindenyltrimethyltitanium;1,2-dimethyl-4,5,6,7-tetrahydroindenyltribenzyltitanium;1,2-dimethyl-4,5,6,7-tetrahydroindenyltitanium trimethoxide;1,3-dimethyl-4,5,6,7-tetrahydroindenyltitanium trichloride;1,3-dimethyl-4,5,6,7-tetrahydroindenyltrimethyltitanium;1,3-dimethyl-4,5,6,7-tetrahydroindenyltribenzyltitanium;1,3-dimethyl-4,5,6,7-tetrahydroindenyltitanium trimethoxide;1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltitanium trichloride;1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltrimethyltitanium;1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltribenzyltitanium;1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltitanium trimethoxide;1,2,3,4,5,6,7-heptamethyl-4,5,6,7-tetrahydroindenyltitanium trichloride;1,2,3,4,5,6,7-heptamethyl-4,5,6,7-tetrahydroindenyltrimethyltitanium;1,2,3,4,5,6,7-heptamethyl-4,5,6,7-tetrahydroindenyltribenzyltitanium;1,2,3,4,5,6,7-heptamethyl-4,5,6,7-tetrahydroindenyltitaniumtrimethoxide; 1,2,4,5,6,7-hexamethyl-4,5,6,7-tetrahydroindenyltitaniumtrichloride;1,2,4,5,6,7-hexamethyl-4,5,6,7-tetrahydroindenyltrimethyltitanium;1,2,4,5,6,7-hexamethyl-4,5,6,7-tetrahydroindenyltribenzyltitanium;1,2,4,5,6,7-hexamethyl-4,5,6,7-tetrahydroindenyltitanium trimethoxide;1,3,4,5,6,7-hexamethyl-4,5,6,7-tetrahydroindenyltitanium trichloride;1,3,4,5,6,7-hexamethyl-4,5,6,7-tetrahydroindenyltrimethyltitanium;1,3,4,5,6,7-hexamethyl-4,5,6,7-tetrahydroindenyltribenzyltitanium;1,3,4,5,6,7-hexamethyl-4,5,6,7-tetrahydroindenyltitanium trimethoxide;octahydrofluorenyltitanium trichloride;octahydrofluorenyltrimethyltitanium;octahydrofluorenyltribenzyltitanium; octahydrofluorenyltitaniumtrimethoxide; 1,2,3,4-tetrahydrofluorenyltitanium trichloride;1,2,3,4-tetrahydrofluorenyltrimethyltitanium;1,2,3,4-tetrahydrofluorenyltribenzyltitanium;1,2,3,4-tetrahydrofluorenyltitanium trimethoxide;9-methyl-1,2,3,4-tetrahydrofluorenyltitanium trichloride;9-methyl-1,2,3,4-tetrahydrofluorenyltrimethyltitanium;9-methyl-1,2,3,4-tetrahydrofluorenyltribenzyltitanium;9-methyl-1,2,3,4-tetrahydrofluorenyltitanium trimethoxide; 9-methyloctahydrofluorenyltitanium trichloride;9-methyloctahydrofluorenyltrimethyltitanium;9-methyloctahydrofluorenyltribenzyltitanium;9-methyloctahydrofluorenyltitanium trimethoxide; any of theabove-mentioned compounds in which the titanium is replaced withzirconium or hafnium and a similar compound in which the transitionmetal element belongs to an other series or lanthanoids. Of these thetitanium compounds are preferable from the viewpoint of catalyticactivity.

The polymerization catalyst for a compound containing an ethylenicallyunsaturated double bond or acetylene series according to the presentinvention comprises the transition metal compound represented by thegeneral formula (I). In particular, the preferable catalysts are apolymerization catalyst which comprises in combination the (A)transition metal compound as previously defined; and (B) at least onemember selected from the group consisting of an (1) oxygen atomcontaining compound, an (2) ionic compound comprising a noncoordinateanion and a cation and an (3) organoboron compound; and a polymerizationcatalyst which comprises in combination the (A) transition metalcompound as previously defined; (B) at least one member selected fromthe group consisting of an (1) oxygen atom containing compound, an (2)ionic compound comprising a noncoordinate anion and a cation and an (3)organoboron compound; and a (C) Lewis acid because of their excellentcatalytic activity.

As the oxygen atom-containing compound as the component (b), there areused such compound having a chain structure represented by the generalformula (I') ##STR2## and/or such compound having a cyclic structurerepresented by the general formula (II') ##STR3##

In the above-mentioned general formula (I') and (II'), Z is a structurein which one or more groups represented by the formula ##STR4## arearranged in an arbitrary order in the number of arbitrary positiveintegers; R^(1'), to R^(9') are each an alkyl group having 1 to 8 carbonatoms and specifically exemplified by methyl group, ethyl group,n-propyl group, isopropyl group, various butyl groups, various pentylgroups, various hexyl groups, various heptyl groups and various octylgroups; R^(1') to R^(9') may be the same as or different; from eachother; Y^(1') and Y^(3') are each a Group 13 metal of the Periodic Tableand specifically exemplified by B, Al, Ga, In and Tl, among which B andAl are preferable; Y^(1') and Y^(3') may be the same as or differentfrom each other; Y^(2') and Y^(4') are each a Group 14 metal of thePeriodic Table and specifically exemplified by C, Si, Ge, Sn and Pb,among which C and Si are preferable; Y^(2') to Y^(4') may be the same asor different from each other;

As the oxygen atom-containing compound represented by the generalformula (I') or (II'), there is preferably usable the reaction productbetween an organoaluminum compound and water, which product isprincipally a chain alkylaluminoxane represented by the general formula(XII) ##STR5## wherein t is a number from 2 to 50 indicatingpolymerization degree and R²⁸ represents an alkyl group having 1 to 8carbon atoms, a cycloalkylaluminoxane having the repeating unitrepresented by the general formula (XIII): ##STR6## wherein R²⁸ is aspreviously defined and the like. Of these alkylaluminoxanes, thatwherein R²⁸ is a methyl group, i.e. methylaluminoxane is particularlypreferred.

As the organoaluminum compound to be reacted with water, mention is madeof an organoaluminum compound represented by the general formula (XIV)

    AIR.sup.28.sub.3                                           (XIV)

wherein R²⁸ is as previously defined, more specifically,trimethylaluminum, triethylaluminum, triisobutylaluminum and the likeand among them trimethylaluminum is particularly desirable.

Generally, the reaction product of an alkylaluminum compound such astrialkylaluminum with water contains the above-mentioned chainalkylaluminoxane and cycloalkylaluminoxane as principal components,unreacted trialkylaluminum, a mixture of various condensation products,and further complicately associated molecules thereof, which becomesvarious products according to the contacting conditions of thetrialkylaluminum compound and water.

The reaction of the trialkylaluminum compound with water is notspecifically limited, but can be performed according to any of knownmethods.

The oxygen atom-containing compound as the component (b) in the presentinvention may be used alone or in combination with at least one otherone. Also there may be used as the component (B) at least one componentof the component (a) in combination with at least one compound of thecomponent (b).

Examples of the ionic compound comprising a noncoordinate anion and acation as the component (2) in the component (B) include a compoundrepresented by the general formula (VII) or (VIII)

    ([L.sup.1 -H].sup.g+).sub.h ([M.sup.1 Y.sup.1 Y.sup.2 - - - Y.sup.n ].sup.(n-m)-).sub.i                                       (VII)

    ([L.sup.2 ].sup.g+).sub.h ([M.sup.2 Y.sup.1 Y.sup.2 - - - Y.sup.n ].sup.(n-m)-).sub.i                                       (VIII)

wherein L² is M³, R⁵ R⁶ M⁴ or R⁷ ₃ C as hereinafter described; L¹ is aLewis base; M¹ and M² are each an element selected from Groups 5 to 15of the Periodic Table and exemplified by B, Al, P, As and Sb; M³ is anelement selected from Groups 8 to 12 of the period Table and exemplifiedby Ag and Cu; M⁴ is an element selected from Groups 8 to 10 of thePeriodic Table an exemplified by Fe, Co and Ni; Y¹ to Y^(n) are each ahydrogen atom, dialkylamino group, alkoxy group, aryloxy group, alkylgroup having 1 to 20 carbon atoms, aryl group having 6 to 20 carbonatoms, aralkyl group, alkylaryl group, substituted alkyl group,organometalloid group or halogen atom and exemplified by dimethylaminogroup, diethylamino group, methoxy group, ethoxy group, butoxy group,phenoxy group, 2,6-dimethylphenoxy group, methyl group, ethyl group,propyl group, butyl group, octyl group, phenyl group, tolyl group, xylylgroup, mesityl group, benzyl group, pentafluorophenyl group,3,5-di(trifluoromethyl)group, 4-tert-butylphenyl group, F, Cl, Br, I,pentamethylantimony group, trimethylsilyl group, trimethylgermyl groupand diphenylboron group; and R⁵ and R⁶ are each a cyclopentadienylgroup, substituted cyclopentadienyl group, indenyl group, substitutedindenyl group or fluorenyl group and exemplified bymethylcyclopentadienyl group and pentamethylcyclopentadienyl group; R⁷is an alkyl group, aryl group or a substituted aryl group, may be thesame or different and exemplified by a phenyl group, 4-methoxyphenylgroup and 4-methylphenyl group; m is the valency of each of M¹ and M²,indicating an integer from 1 to 7; n is an integer from 2 to 8; g is theion valency of each of [L¹ -H] and [L² ], indicating an integer from 1to 7; h is an integer of 1 or greater and i=(h×g)/(n-m).

Examples of the noncoordinate anion in the aforestated ionic compoundinclude (tetraphenyl)borate; tetra(fluorophenyl)borate;tetrakis(difluorphenyl)borate; tetrakis(trifluorophenyl)borate;tetrakis(tetrafluorophenyl)borate; tetrakis(pentafluorophenyl)borate;tetrakis(trifluoromethylphenyl)borate; tetra(tolyl)borate;tetra(xylyl)borate; (triphenylpentafluorophenyl)borate;[tris(pentafluorophenyl)phenyl]borate and tridecahydride-7,8-dicarbaundecaborate.

Examples of the cation in the above-mentioned ionic compound includetriethyl ammonium; tributyl ammonium; N,N'-dimethylanilinium;N,N'-diethylanilinium; triphenylphosphinium; dimethylphenylphosphinium;1,1'-dimethylferrocene; decamethylferrocene; silver (I);triphenylcarbenium; tritolylcarbenium; trimethoxyphenylcarbenium;(ditolylphenyl)carbenium; [di(methoxyphenyl)phenyl]carbenium and[methoxyphenyl di(phenyl)]carbenium.

The above-mentioned ionic compound can preferably be used by optionallyselecting the noncoordinate anion and cation from among theabove-exemplified examples and combining the selected ones.

Among the compounds represented by the general formula (VII) or (VIII),specific examples of preferably usable compounds include, as thecompound of general formula (VII), triethylammonium tetraphenylborate,tri(n-butyl) ammonium tetraphenylborate; trimethylammoniumtetraphenylborate, triethylammonium tetrakis(pentafluorophenyl)borate,tri(n-butyl)ammonium tetrakis(pentafluorophenyl)borate, triethylammoniumhexafluoroarsenate, etc., and as the compound of general formula (VIII),pyridinium tetrakis(pentafluorophenyl)borate, pyrroliniumtetrakis(pentafluorophenyl)borate, N,N-dimethylaniliniumtetrakis(pentafluorophenyl)borate, methyldiphenylammoniumtetrakis(pentafluorophenyl)borate, ferrocenium tetraphenylborate,dimethylferrocenium tetrakis(pentafluorophenyl)borate, ferroceniumtetrakis(pentafluorophenyl)borate, decamethylferroceniumtetrakis(pentafluorophenyl)borate, acetylferroceniumtetrakis(pentafluorophenyl)borate, formylferroceniumtetrakis(pentafluorophenyl)borate, cyanoferroceniumtetrakis(pentafluorophenyl)borate, silver tetraphenylborate, silvertetrakis(pentafluorophenyl)borate; trityl tetraphenylborate, trityltetrakis(pentafluorophenyl)borate, silver hexafluoroarsenate, silverhexafluoroantimonate, silver tetrafluoroborate, etc.

Examples of the organoboron compounds usable as the component (3)include the compound represented by the general formula (IX)

    R.sup.8.sub.3 BL.sup.3.sub.v                               (IX)

wherein R⁸ is an aliphatic hydrocarbon group having 1 to 20 carbonatoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, asubstituted aromatic hydrocarbon group, hydrogen atom or a halogen atom,may be the same or different and specifically exemplified by a phenylgroup, tolyl group, fluorophenyl group, trifluoromthylphenyl group,pentafluorophenyl group, fluorine atom, chlorine atom, bromine atom andiodine atom; L³ is a Lewis base and exemplified by an ether compoundsuch as diethyl ether and tetrahydrofuran and an amine compound such aspyridine; and v is an integer from 0 to 3. Specific examples thereofinclude triphenylboron, tris(pentafluorophenyl)boron, triethylboron,di(pentafluorophenyl)phenylboron andtris(3,5-ditrifluoromethylphenyl)boron.

As the aforesaid component (B) in the polymerization catalyst accordingto the present invention, the aluminoxane as the component (1) may beused alone or in combination with at least other one, the ionic compoundas the component (2) may be used alone or in combination with at leastother one, the organoboron compound as the component (3) may be usedalone or in combination with at least other one, and in addition, thecomponents (1), (2) and (3) may be used in optional combination witheach other.

Examples of the Lewis acid as the component (C) to be used when desiredin the polymerization catalyst according to the present inventioninclude an organoaluminum compound, a magnesium compound, zinc compoundand lithium compound.

Specific examples of the above-mentioned organoaluminum compound includethe compound represented by the general formula (X)

    R.sup.9.sub.r Al(OR.sup.10).sub.s H.sub.t Z.sub.u          (X)

wherein R⁹ and R¹⁰ independently of one another, are each an alkyl grouphaving 1to 8 carbon atoms and may be the same or different; Z is anhalogen atom; r, s, t and u each satisfy the relations 0<r≦3, 0<s≦3,0≦t<3 and 0≦u<3 and r+s+t+u=3.

In the organoaluminum compound represented by the general formula (IX),the compound wherein s=t=u=0 and r=3 is exemplified bytrimethylaluminum, triethylaluminum, triisopropylaluminum,triisobutylaluminum and trioctylaluminum. In the case of t=u=0 and1.5<r≦3, the compound is exemplified by diethylaluminum ethoxide,dibutylaluminum butoxide, diethylaluminum sesquiethoxide anddibutylaluminum sesquibutoxide; as well as partially alkoxylatedalkylaluminum.

Examples of the compound corresponding to the case where s=t=0 includediethylaluminum dichloride and dibutulaluminum dichloride (r=2);ethylaluminum sesquichloride and butylaluminum sesquichloride (r=1.5);and ethylaluminum dichloride and butylaluminum dichloride (r=1).

Examples of the compound corresponding to the case in which s=u=0include diethylaluminum hydride and diisobutylaluminum hydride (r=2);and ethylaluminum dihydride and butylaluminum dihydride (r=1).

Examples of the above-mentioned magnesium compound include a Grignardcompound such as methylmagnesium bromide, ethylmagnesium bromide,phenylmagnesium bromide and benzylmagnesium bromide, an organomagnesiumcompound such as diethoxymagnesium and ethylbutylmagnesium and aninorganic magnesium compound such as magnesium chloride. In addition,mention may be made of a zinc compound exemplified by an organozinccompound such as diethylzinc and of a lithium compound exemplified by anorganolithium compound such as methyllithium.

As a method for contact-mixing the components (A) and (B) and thecomponent (C) to be used when desired, mention may be made of 1 a methodin which the component (C) is added to the contact mixture between thecomponents (A) and (B) to form a catalyst, which is brought into contactwith a monomer component to be polymerized; 2 a method in which thecomponent (A) is added to the contact mixture between the components (B)and (C) to form a catalyst, which is brought into contact with a monomercomponent to be polymerized; 3 a method in which the component (B) isadded to the contact mixture between the components (A) and (C) to forma catalyst, which is brought into contact with a monomer component to bepolymerized; 4 a method in which the components (A), (B) and (C) areeach separately brought into contact with a monomer component to bepolymerized; and 5 a method in which the catalyst prepared in theabove-mentioned 1, 2 or 3 is brought into contact with the contactmixture between the monomer component to be polymerized and thecomponent (C).

The contact mixing among the components (A) and (B) and the component(C) to be used as desired can be carried out at a temperature in therange of -20° to 200° C., needles to say, at a polymerizationtemperature.

The polymerization catalyst comprising in combination the components (A)and (B) or the components (A), (B) and (C) may be further incorporatedwith an other catalyst component.

The blending ratio of the catalyst components varies depending uponvarious conditions and thus can not unequivocally be determined.However, when the component (B) is aluminoxane, the molar ratio of thecomponent (A) to the component (B) is selected so as to be 1:1 to1:10,000, preferably 1:1 to 1:1,000. In the case where the component (B)is an ionic compound comprising a noncoordinate anion and a cation, oran organoboron compound, the molar ratio of the component (A) to thecomponent (B) is preferably selected so as to be 0.1:1 to 1:0.1. Themolar ratio of the component (A) to the component (C) when used, isselected so as to be 1:0.1 to 1:1,000.

The polymerization catalyst according to the present invention is usedfor the polymerization of acetylene series or a compound containing anethylenically unsaturated double bond, which is exemplified by anolefin, a diolefin compound and styrene series.

Examples of such olefin include α-olefins such as ethylene; propylene;butene-1; pentene-1; hexene-1; heptene 1; octene-1; nonene-1; decene-1;4-phenylbutene-1; 6-phenylhexene-1; 3-methylbutene-1; 4-methylpentene-1;3-methylpentene-1; 3-methylhexene-1; 4-methylhexene-1; 5-methylhexene-1;3,3-dimethylpentene-1; 3,4-dimethylpentene-1; 4,4-dimethylpentene-1; andvinylcyclohexane, halogen-substituted α-olefins such ashexafluoropropene; tetrafluroethylene; 2-fluoropropene; fluoroethylene;1,1difluoroethylene; 3-fluoropropene; trifluoroethylene; and3,4-dichlorobutene-1, cyclic olefins such as cyclopentene; cyclohexene;norbornene; 5-methylnorbornene; 5-ethylnorbornene; 5-propylnorbornene;5,6-dimethylnorbornene; 1-methylnorbornene; 7-methylnorbornene;5,5,6-trimethylnorbornene; 5-phenylnorbornene; and 5-benzylnorbornene.

Examples of the diolefin compound include straight chain diolefins suchas butadiene; isoprene; and 1,6-hexadiene, and cyclic diolefins such asnorbornadiene; 5-ethylidenenorbornene; 5-vinylnorbornene;5-vinylcyclohexene; and dicyclopentadiene.

Examples of the styrene series include styrene, alkylstyrenes such asp-methylstyrene; m-methylstyrene; omethylstyrene; 2,4-dimethylstyrene;2,5-dimethylstyrene; 3,4-dimethylstyrene, 3,5-dimethylstyrene; andp-tertiarybutylstyrene; alkoxystyrenes such as p-methoxystyrene;m-methoxystyrene; and o-methoxystyrene; halogenated styrenes such asp-chlorostyrene; m-chlorostyrene; o-chlorostyrene; p-bromostyrene;m-bromostyrene; o-bromostyrene; p-fluorostyrene; m-fluorostyrene;o-fluorostyrene and o-methyl-p-fluorostyrene; organosiliconatedsytrenes, vinylbenzoic acid esters and divinylbenzene.

Examples of the acetylene series include acetylene, methylacetylene,phenylacetylene and trimethylsilylacetylene.

The above-mentioned monomer may be polymerized alone or in combinationwith at least one other monomer.

The polymerization method may be bulk polymerization method withoutspecific limitation. The polymerization may be carried out in analiphatic hydrocarbon solvent such as pentane, hexane and heptane, analicyclic hydrocarbon solvent such as cyclohexane or an aromatichydrocarbon solvent such as benzene, toluene, xylene and ethylbenzene.

The polymerization temperature is not specifically limited but isusually 0° to 200° C., preferably 20° to 100° C. In the case where agaseous monomer is employed, the partial pressure of the gaseous monomeris usually 300 kg/cm₂ (29.4199×10⁶ Pa) or lower; preferably 30 kg/cm²(2.941×10⁶ Pa) or lower.

It is preferable in the present invention that the above-mentionedcatalyst be employed for the production of a styrenic polymer inparticular. In this case, a styrenic monomer may be homopolymerized orcopolymerized with at least one other comonomer. In addition, at leastone styrenic monomer may be copolymerized with at least onepolymerizable unsaturated compound, which is exemplified by olefin,diolefin compound and acetylene series.

The styrenic polymer obtained by the use of the above-mentioned catalysthas a high degree of syndiotactic configuration in its styrenic chain.In this case, a high degree of syndiotactic configuration in thesytrenic chain of the styrenic polymer signifies that its stereochemicalstructures is of high degree of syndiotactic configuration, i,e., thestereo-structure in which phenyl groups or substituted phenyl groups asside chains are located alternately at opposite directions relative tothe main chain consisting of carbon-carbon bonds. Tacticity isquantitatively determined by the nuclear magnetic resonance method (¹³C-NMR method) using carbon isotope. The tacticity as determined by the¹³ C-NMR method can be indicated in terms of proportions of structuralunits continuously connected to each other, i.e., a diad in which twostructural units are connected to each other, a triad in which threestructural units are connected to each other and a pentad in which fivestructural units are connected to each other. "The styrenic polymershaving such a high degree of syndiotactic configuration" as mentioned inthe present invention usually means polystyrene, poly(substitutedstyrene), poly(vinyl benzoate), the mixture thereof, and copolymerscontaining the above polymers as main components, having such asyndiotacticity that the proportion of racemic diad is at least 75%,preferably at least 85%, or the proportion of racemic pentad is at least30%, preferably at least 50%. The poly(substituted styrene) includespoly(hydrocarbon group-substituted styrene) such as poly(methylstyrene),poly(ethylstyrene), poly(isopropylstyrene), poly(phenylstyrene) andpoly(vinylstyrene); poly(halogenated styrene) such aspoly(chlorostyrene), poly(bromostyrene), and poly(fluorostyrene); andpoly(alkoxystyrene) such as poly(methoxystyrene) andpoly(ethoxystyrene). Examples of the particularly preferable styrenicpolymers among them include polystyrene, poly(n-methylstyrene),poly(m-methylstyrene), poly(p-tertiary-butylstyrene),poly(p-chlorostyrene), poly(m-chlorostyrene), poly(p-fluorostyrene) anda copolymer of styrene and p-methylstyrene.

By virtue of its specific constitution having, as a ligand, a fusedpolycyclic cyclopentadienyl group in which at least one of many-memberedrings to which cyclopentadienyl groups are fusedly bonded is a saturatedbone, the transition metal compound according to the present inventionis useful as a component of a polymerization catalyst for a compoundcontaining an ethylenically unsaturated double bond or acetylene series,especially for styrene series.

In addition, the polymerization catalyst comprising the above-mentionedtransition metal compound has a high activity and is preferably used forthe polymerization of a compound containing an ethylenically unsaturateddouble bond or acetylene series. In particular, by homopolymerizing orcopolymerizing styrene series by the use of the aforesaid polymerizationcatalyst, there is obtained a styrenic polymer having a high degree ofsyndiotactic configuration and minimized in the amounts of residualmetals at a low cost in high efficiency.

In the following, the present invention will be described in more detailwith reference to non-limitative examples.

EXAMPLE1 Synthesis of 1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltitaniumtrichloride (Compound A)

(1) Synthesis of 2,3-dimethyl-4,5,6,7-tetrahydroinde-1-one

In 500 g of polyphosphonic acid were added 32.9 g (400 mmol) ofcyclohexene and 40.3 g of the tiglic acid with heating to 60° C. andstirring for 2 hours. After temperature lowering, the resultant reddishyellow viscous solution was added dropwise to 1000 milliliter(hereinafter abbreviated to "mL") of water to form yellow suspension,which was then extracted with 700 mL of ethyl ether, separated andwashed with saturated aqueous solution of sodium chloride. Thus, theresultant organic phase was dried with magnesium sulfate. anhydride.After the separation of the drying agent, the solvent was distilled awayand the resultant product was distilled under reduced pressure to obtain39.2 g of the objective product from the fraction at 85° to 87° C. under3 mm

(2)Synthesis of 1,2,3-trimethyl-4,5,6,7-tetrahydroinde-1-ol

In 100 mL of dried diethyl ether were added 16.2 g (99.6 mmol) of2,3-dimethyl-4,5,6,7-tetrahydroinde-1-one as obtained in the foregoingstep (1) and further 100 mL of solution of 1.4 M methyllithium indiethyl ether to proceed with reaction at room temperature for one hour,followed by refluxing with heating for 15 hours. After temperaturelowering, a small amount of water was added to the reaction system, andthe resultant organic phase was separated and dried with magnesiumsulfate anhydride. After the separation of the drying agent, the solventwas distilled away to obtain 15.3 g of the objective product in the formof pale yellow oil.

(3) Synthesis of 1,2,3-trimethyl-4,5,6,7-tetrahydroindene

15.3 g of 1,2,3-trimethyl-4,5,6,7-tetrahydroinde-1-ol as obtained in theforegoing step (2) was diluted with 150 mL of dehydrated ethyl ether,incorporated with several drops of 12 N hydrochloric acid and stirred atroom temperature for 2 hours. The resultant mixture was washed with 100mL of water 3 times and separated into organic phase, which was driedwith magnesium sulfate anhydride. After the separation of the dryingagent, the solvent was distilled away at atmospheric pressure to obtain14.05 g of 1,2,3-trimethyl-4,5,6,7-tetrahydroindene.

(4) Synthesis of1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltrimethylsilane

14.05 g of 1,2,3-trimethyl-4,5,6,7-tetrahydroindene as obtained in theforegoing step (3) was dissolved in 50 mL of dehydrated tetrahydrofuran.To the resultant solution was added dropwise under ice cooling 75 mL ofsolution of 1.6 M butyllithium in hexane, followed by stirring for 12hours at room temperature restored. Subsequently the volatile matters inthe mixed solution were distilled away at room temperature under reducedpressure, and the resultant solid was washed with hexane to producewhite 1,2,3-trimethyl-4,5,6,7-tetrahydroindenyllithium, which was againdissolved in 100 mL of dehydrated tetrahydrofuran. To the resultantsolution was added under ice cooling, trimethylchlorosilane which hadbeen subjected to simple distillation, followed by stirring at roomtemperature for one day and night. Subsequently the volatile matters inthe mixed solution were distilled away at room temperature under reducedpressure and the nonvolatile solution was extracted with 300 mL ofhexane. The insoluble portion was filtered away and the hexane wasdistilled away under reduced pressure from the solution in hexane torecover 18.1 g (77.1 mmol) of1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltrimethylsilane in the form ofpale yellow oil.

(5) Synthesis of 1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltitaniumtrichloride.

Titanium tetrachloride in an amount of 18.9 g was dissolved in 150 mL ofdehydrated toluene. To the resultant solution was added dropwise 18.1 gof 1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltrimethylsilane which hadbeen obtained in the foregoing step (4) and diluted with 40 mL of##STR7## dehydrated toluene. Thereafter, the mixed solution was broughtinto reaction at room temperature for 3 hours, followed by furtherreaction under refluxing for one hour to obtain dark red solution.Subsequently, the temperature in the reaction system was lowered to 90°C., the insoluble portion was filtered away and the volatile matters inthe filtrate were distilled away under reduced pressure to obtain brownsolid. The solid was washed with 50 mL of hexane at room temperature,followed by distillation under reduced pressure to recover1,2,3-trimethyl-4,5,6,7-tetrahydroindenltitanium trichloride in the formof dark red solid, which was recrystallized from hexane to obtain 10.5(33 mmol) of acicular crystal as the objective product.

The objective product was analyzed by ¹ H-NMR, ¹³ C-NMR and ⁴⁷ Ti, ⁴⁹Ti-NMR with the results as follows.

¹ H-NMR (trimethylsilane as standard, heavy chloroform (CDCl₃) assolvent):

3.223 to 3.282 ppm (2H, m), 2.573 to 2.647 ppm (2H, m), 2.443 ppm (3H,s), 2.307 ppm (6H, s), 2.009 ppm (2H, m), 1.731 ppm (2H, m)

¹³ C-NMR (tetramethylsilane as standard, heavy chloroform (CDCl₃) assolvent):

140.00 ppm, 137.73 ppm, 135.03 ppm, 25.63 ppm, 21.87 ppm, 14.52 ppm,13.72 ppm

⁴⁷ Ti, ⁴⁹ Ti-NMR (Chemical shift of ⁴⁷ Ti in TiCl₄ as standard, heavychloroform (CDCl₃) as solvent:

⁴⁷ Ti: 347.10 ppm

⁴⁹ Ti: 80.730 ppm

The schematic synthesis process for Compound A is illustrated asfollows: ##STR8##

EXAMPLE 2 Synthesis of1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltrimethyltitanium (Compound B)

1.58 g (5.0 mmol) of 1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltitaniumtrichloride was dissolved in 30 mL of dehydrated tetrahydrofuran, and tothe resultant solution was added under ice cooling, 16 mL of solution of1.0 M methylmagnesium bromide in tetrahydrofuran with stirring for 30minutes. Subsequently the volatile matters in the mixed solution weredistilled away at room temperature under reduced pressure to obtainbrown solid, from which soluble matter in 150 mL of hexane was extractedand insoluble matter was filtered away. Thereafter the hexane wasdistilled away from the filtrate under reduced pressure to obtain 1.32 gof brown oil, which was1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltrimethyltitanium and wasgradually crystallized at -4° C. The product was analyzed by ¹ H-NMR and¹³ C-NMR with the results as follows:

¹ H-NMR (trimethylsilane as standard, heavy chloroform (CDCl₃) assolvent)

2.57 ppm (2H, br), 2.40 ppm (2H, br), 1.99 ppm(3H, s),

1.921 ppm (6H, s), 1.706 ppm(4H, br), 0.832 ppm (9H, s)

¹³ C-NMR (tetramethylsilane as standard, heavy chloroform (CDCl₃) assolvent)

123.90 ppm, 122.83 ppm, 120.23 ppm, 61.56 ppm,

23.62 ppm, 22.98 ppm, 11.81 ppm, 11.44 ppm

EXAMPLE 3 Synthesis of 1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltitaniumtrimethoxide (Compound C)

(1) Synthesis of1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltrimethylsilane

19.6 g of 1,2,3-trimethyl-4,5,6,7-tetrahydroindene as obtained inExample 1-(3) was dissolved in 70 mL of tetrahydrofuran anhydride. Thenthe resultant solution was added dropwise at room temperature to 200 mLof suspension of 7.2 g of potassium hydride in tetrahydrofurananhydride. After the elapse of 1.5 hour, the mixed solution wasgradually heated and the reaction was continued under refluxing withheating for 4 hours. When hydrogen was no longer generated, the reactionsolution was restored to room temperature, incorporated with 19.6 g oftrimethylsilyl chloride and stirred for two days and nights.Subsequently water was added to the reaction liquid to stabilize theexcess potassium hydride, then the organic phase was separated,extraction was carried out from the water phase by the use of ethylether and the mixture of the extract and the aforesaid organic phase wasdried with magnesium sulfate anhydride. Lastly, vacuum distillation wasperformed to recover 22.7 g of1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltrimethylsilane.

(2) Synthesis of 1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltitaniummethoxide

Titanium tetrachloride in an amount of 22.8 g was dissolved in 150 mL ofdehydrated toluene. To the resultant solution was added dropwise 22.7 gof 1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltrimethylsilane which hadbeen obtained in the foregoing step (1) and diluted with 70 mL ofdehydrated toluene. Thereafter, the mixed solution was brought intoreaction at room temperature for 4 hours, followed by further reactionunder refluxing for one hour to obtain dark red solution. Subsequently,the temperature in the reaction system was lowered to 90° C., theinsoluble portion as filtered away and the filtrate was incorporated,under ice cooling, with 16.2 g of dehydrated methanol and 50.8 g ofdehydrated triethylamine, followed by stirring one day and night.Thereafter, the volatile matters in the mixture were distilled awayunder reduced pressure, the resultant nonvolatile mixture wasincorporated with hexane, the insoluble portion was filtered away, thesolvent was removed from the filtrate, vacuum distillation was appliedto the mixture and the fraction of 128° to 129° C. in boiling pointunder 1 mm Hg was collected to recover 9.73 g of1,2,3-trimethyl-4,5,6,7-tetrahydroindenyltitanium trimethoxide in theform of yellow oil. The objective product was analyzed by ¹ H-NMR and ¹³C-NMR with the results as follows:

¹ H-NMR (trimethylsilane as standard, heavy chloroform (CDCl₃) assolvent)

4.07 ppm (9H, s), 2.62 ppm (2H, m), 2.42 ppm (2H, m),

2.04 ppm (3H, s), 2.00 ppm (6H, s), 1.62 ppm to 18.4 ppm (4h, m)

¹³ C-NMR (tetramethylsilane as standard, heavy chloroform (CDCl₃) assolvent)

124.52 ppm, 123.44 ppm, 119.38 ppm, 61.40 ppm, 23.00 ppm,

22.62 ppm, 10.52 ppm, 10.00 ppm

EXAMPLE 4 (polymerization of styrene)

In a 30 mL glass ampule which had been dried and purged with nitrogenwere placed 10 mL of styrene, 200 μL of 0.5 mol/L solution oftriisobutylaluminum in toluene and 100 μL of 1 mol/L solution ofaluminoxane in toluene, followed by sealing the ampule with a tefloncap. Then the ampule was immersed in an oil bath at 70° C. and allowedto stand for 10 minutes. Then, to the resultant mixture was added 50 μLof 10 mmol/L of the Compound A as obtained in Example 1 in toluene toproceed with polymerization at 70° C. for 2 hours. After the completionof the reaction, the content in the ampule was washed with methanol anddried to recover 6.87 g of polymer with a catalytic activity of 287kg/g-Ti. The polymer was subjected to Soxhlet extraction for 5 hours bythe use of boiling methyl ethyl ketone to produce 6.80 g of syndiotacticpolystyrene from the insoluble portion. The objective product was ahighly stereoregular syndiotactic polystyrene having a weight-averagemolecular weight of 335,300, a molecular-weight distribution of 2.3, atleast 95% syndiotacticity in terms of racemic pentad and a crystalmelting point of 270° C.

COMPARATIVE EXAMPLE 1

The procedure in Example 4 was repeated to carry out the polymerizationexcept that 1,2,3-trimethylindenyltitanium trichloride was used in placeof the Compound A. As a result, 2.40 g of a syndiotactic polystyrenehaving a weight-average molecular weight of 250,000 was obtained with acatalytic activity of 100 kg/g-Ti, which was remarkably low as comparedwith the results in Example 4.

EXAMPLE 5 (polymerization of styrene)

The procedure in Example 4 was repeated to carry out the polymerizationexcept that the polymerization temperature was set on 60° C. As aresult, 7.24 g of a syndiotactic polystyrene having a weight-averagemolecular weight of 426,000 was obtained with a catalytic activity of302 kg/g-Ti.

EXAMPLE 6 (polymerization of styrene)

The procedure in Example 4 was repeated to carry out the polymerizationexcept that the polymerization temperature was set on 80° C. As aresult, 6.18 g of a syndiotactic polystyrene having a weight-averagemolecular weight of 284.700 was obtained with a catalytic activity of260 kg/g-Ti.

COMPARATIVE EXAMPLE 2

The procedure in Example 6 was repeated to effect the polymerizationexcept that pentamethylcyclopentadienyltitanium trichloride was used inplace of the Compound A. As a result, 4.90 g of a syndiotacticpolystyrene having a weight-average molecular weight of 284,000 (almostthe same as that in Example 6) was obtained with a catalytic activity of204 kg/g-Ti, which was considerably low as compared with the results inExample 6.

EXAMPLE 7 (polymerization of styrene)

The procedure in Example 5 was repeated to perform the polymerizationexcept that the Compound C as obtained in Example 3 was used in place ofthe Compound A. The resultant polymer in an amount of 6.95 g wassubjected to Soxhlet Extraction for 5 hours by the use of boiling methylethyl ketone to produce 686 g of syndiotactic polystyrene from theinsoluble portion with a catalytic activity of 286 kg/g-Ti. It had aweight-average molecular weight of 453,000.

EXAMPLE 8 (polymerization of styrene)

N,N-dimethylaniliniumtetrakis(pentafluorophenyl)borate in an amount of0.064 g was suspended in 31.6 mL of toluene, and the resultantsuspension was incorporated with 0.4 mL of 2.0 mol/L solution oftriisobutylaluminum in toluene and then with 8 mL of 10 mmol/L solutionof the Compound B as obtained in Example 2 in toluene to prepare acatalyst solution.

Subsequently, in a glass ampule were placed 10 mL of styrene and 20 μLof 0.5 mol/L solution of triisobutylaluminum in toluene, followed bysealing the ampule with a teflon cap. The content in the ampule washeated to 70° C. and incorporated with 188 μL of the above-preparedcatalyst solution to preceed with polymerization at 70° C. for 4 hours.After the completion of the reaction, the content was washed withmethanol and dried to recover 5.17 g of polymer with a catalyticactivity of 288 kg/g-Ti. The polymer was subjected to Soxhlet extractionfor 5 hours by the use of boiling methyl ethyl ketone to produce 5.08 gof syndiotactic polystyrene from the insoluble portion. The objectivesyndiotactic polystyrene had a weight-average molecular weight of906,000.

What is claimed is:
 1. A polymerization catalyst for a compound containing an ethylenically unsaturated double bond or an acetylenic bond, which catalyst comprises:(A) a transition metal compound represented by formula (I)

    RMX.sub.a-1 L.sub.b                                        (I)

wherein R is, as a π ligand, a fused bicyclic or tricyclic cyclopentadienyl group in which at least one of many-membered rings to which a cyclopentadienyl group is fusedly bonded is a saturated ring; M is a transition metal, X is a σ ligand, a plurality of moieties X may be the same or different, L is a Lewis base, a is the valency of moiety M, b is 0, 1 or 2 and when L is a plurality, each L may be the same or different; and (B) an aluminoxane.
 2. A polymerization catalyst for a compound containing an ethylenically unsaturated double bond or an acetylenic bond, which catalyst comprises:(A) a transition metal compound represented by formula (I)

    RMX.sub.a-1 L.sub.b                                        (I)

wherein R is, as a π ligand, a fused bicyclic or tricyclic cyclopentadienyl group in which at least one of many-membered rings to which a cyclopentadienyl group is fusedly bonded is a saturated ring; M is a transition metal, X is a σ ligand, a plurality of moieties X may be the same or different, L is a Lewis base, a is the valency of moiety M, b is 0, 1 or 2 and when L is a plurality, each L may be the same or different; component (B) is at least one member selected from the group consisting of an (1) aluminoxane, (2) an ionic compound comprising a noncoordinating anion and a cation, and (3) an organoboron compound; and (C) a Lewis acid.
 3. A polymerization catalyst for a compound containing an ethylenically unsaturated double bond or an acetylenic bond, which catalyst comprises:(A) a transition metal compound represented by formula (I)

    RMX.sub.a-1 L.sub.b                                        (I)

wherein R is, as a π ligand, a fused bicyclic or tricyclic cyclopentadienyl group in which at least one of many-membered rings to which a cyclopentadienyl group is fusedly bonded is a saturated ring; M is a transition metal, X is a σ ligand, a plurality of moieties X may be the same or different, L is a Lewis base, a is the valency of moiety M, b is 0, 1 or 2 and when moiety L is a plurality, each L may be the same or different; and component (B) is an ionic compound comprising a non-coordinating anion and a cation; and component (C) is a Lewis acid.
 4. The .[.transition metal compound.]. .Iadd.polymerization catalyst .Iaddend.according to claim 1, wherein R .Iadd.of said transition metal compound .Iaddend.is selected from the fused polycyclic cyclopentadienyl group represented by any one of formulae (II) to (IV) ##STR9## wherein R¹, R² and R³ are each hydrogen, halogen, an aliphatic hydrocarbon group having 2 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxyl group having 6 to 20 carbon atoms, a thioalkoxyl group having 1 to 20 carbon atoms, a thioaryloxyl group having 6 to 20 carbon atoms, an amino group, an amide group, a carboxyl group or an alkylsilyl group and may be the same as or different from each other; and c, d, e and f are each an integer of one or greater.
 5. The .[.transition metal compound.]. .Iadd.polymerization catalyst .Iaddend.according to claim 2, wherein R .Iadd.of said transition metal compound .Iaddend.is selected from the fused polycyclic cyclopentadienyl group represented by any one of formulae (II) to (IV) ##STR10## wherein R¹, R² and R³ are each hydrogen, halogen, an aliphatic hydrocarbon group having 2 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxyl group having 6 to 20 carbon atoms, a thioalkoxyl group having 1 to 20 carbon atoms, a thioaryloxyl group having 6 to 20 carbon atoms, an amino group, an amide group, a carboxyl group or an alkylsilyl group and may be the same as or different from each other; and c, d, e and f are each an integer of one or greater.
 6. The .[.transition metal compound.]. .Iadd.polymerization catalyst .Iaddend.according to claim 3, wherein R .Iadd.of said transition metal compound .Iaddend.is selected from the fused polycyclic cyclopentadienyl group represented by any one of formulae (II) to (IV) ##STR11## wherein R¹, R² and R³ are each hydrogen, halogen, an aliphatic hydrocarbon group having 2 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxyl group having 6 to 20 carbon atoms, a thioalkoxyl group having 1 to 20 carbon atoms, a thioaryloxyl group having 6 to 20 carbon atoms, an amino group, an amide group, a carboxyl group or an alkylsilyl group and may be the same as or different from each other; and c, d, e and f are each an integer of one or greater.
 7. The polymerization catalyst of claim 4, wherein R is a 4,5,6,7-tetrahydroindenyl group.
 8. The polymerization catalyst of claim 5, wherein R is a 4,5,6,7-tetrahydroindenyl group.
 9. The polymerization catalyst of claim 6, wherein R is a 4,5,6,7-tetrahydroindenyl group.
 10. A process for producing a polymer of a compound containing an ethylenically unsaturated double bond or a polymer of an acetylenic compound, which comprises:polymerizing said ethylenically unsaturated compound or said acetylenic compound in the presence of the polymerization catalyst of claim
 1. 11. A process for producing a polymer of a compound containing an ethylenically unsaturated double bond or a polymer of an acetylenic compound, which comprises:polymerizing said ethylenically unsaturated compound or said acetylenic compound in the presence of the polymerization catalyst of claim
 2. 12. A process for producing a polymer of a compound containing an ethylenically unsaturated double bond or a polymer of an acetylenic compound, which comprises:polymerizing said ethylenically unsaturated compound or said acetylenic compound in the presence of the polymerization catalyst of claim
 3. 13. A process for producing a styrenic polymer, which comprises:copolymerizing a styrenic monomer and another polymerizable unsaturated compound in the presence of the polymerization catalyst of claim
 1. 14. A process for producing a styrenic polymer, which comprises:copolymerizing a styrenic monomer and another polymerizable unsaturated compound in the presence of the polymerization catalyst of claim
 2. 15. A process for producing a styrenic polymer, which comprises:copolymerizing a styrenic monomer and another polymerizable unsaturated compound in the presence of the polymerization catalyst of claim
 3. 16. The process of claim 13, wherein said styrenic polymer exhibits a high degree of syndiotacticity.
 17. The process of claim 14, wherein said styrenic polymer exhibits a high degree of syndiotacticity.
 18. The process of claim 15, wherein said styrenic polymer exhibits a high degree of syndiotacticity. 